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Miscellaneous Notices to Mariners

Last updated: 12.04.19

Important notices and information about the use of the Norwegian NM, Etterretninger for sjøfarende (Efs) can be found here. The Norwegian Hydrographic Service emphasizes that the complete pdf version the Efs is the official document.

1 Important attachments to the Efs

The attachments will be published in their entirety in the first edition of the Norwegian Notices to Mariners, Etterretninger for sjøfarende (Efs), every year.

It is important that you as seafarers regularly read these attachments, as changes may occur.

The Norwegian Hydrographic Service emphasizes that the complete pdf version of the Efs is the official document. Professional users/subscribers are responsible for downloading the latest pdf version of the Efs from the Internet service at

Quality in Norwegian Charts

Electronic navigational charts (ENC) and paper charts contain data of different quality. Many areas consist of a mixture of modern and older data. In electronic charts Zones of Confidence are used to indicate the quality of the data presented. In paper charts, data quality is shown in a source diagram.

Quality of Norwegian Charts in the Waters Around Svalbard

Uncritical use of older charts and modern positioning systems (like GPS) can, because of discrepancies etc. related to the datum, lead to serious mistakes (several hundred meters) during navigation. This further means that the safety margin that sailors should always apply may not be in place as expected.

In some of the older charts, information is given showing the displacement between the graticule of the chart and the World Geodetic System (WGS-84).

New charts for the area are made in accordance to the World Geodetic System (WGS84), while new prints of the older charts retain the existing graticule.

The Norwegian Hydrographic Service reminds the users that the paper charts in the area are on a scale of 1:100 000 or less, and that these charts often form the basis for electronic charts over these waters.

For general information about the quality of the charts around Svalbard, reference is made to The Norwegian Pilot, Volume 7 and the information given in each chart.

The users should be aware that all given corrections (shifts in datum) must be considered to be approximate. The coastline can have considerable discrepancies when compared to the graticule of the chart. Furthermore, the lines of survey for these waters are spaced out to such a degree that the occurrence of undiscovered shoals and rocks cannot be excluded.

Accordingly, navigation in these waters requires extra caution. The navigator should, in keeping with established navigational traditions, use all accessible navigation aids (including radar), continuously compare the observations from the different aids, remain vigilant and ensure that the navigation at all time is carried out applying a sufficient safety margin.

Use of electronic charts does not relieve the navigator from these tasks, and will still require the same professional and critical attitude as with traditional navigation using paper charts.

Changes in glacier fronts and coastline – glaciers used in conjunction with leading lines

The glacier fronts seawards are continually changing. In general, the glacier fronts are receding: observations exist where the glaciers have receded several hundred meters during the last decades.

It is also usual that the glaciers have shorter periods when advancing considerably ("surging glaciers"). Large quantities of ice then move downward from the top of the glacier and collapse below. For this reason contour lines and terrain close to the glacier can deviate from contour lines on the chart. As an example the Fridtjovbreen in van Mijenfjorden advanced about four kilometres from autumn 1995 and the next two and a half years.

In the chart the glacier fronts seawards can refer to a certain year, but such information does not always exist. Changes in the front of a glacier can cause a considerable difference between the existing front and the charted front. In areas where the glacier fronts have receded compared to fronts shown on the chart, no depth information exists.

Also the coastline can change, in particular close to large rivers. The user should bear this in mind and ensure that the utmost care is taken when navigating close to glacier fronts and river estuaries.

Glaciers are in some cases used as a reference in conjunction with leading lines. These can be old and well-known points which have been used for decades. Changes in the form and outline of glaciers might, however, cause changes in the reference point. Where glaciers are used as reference points great care must be taken during the navigation, and it must always be done in conjunction with other navigation aids.

Unsurveyed areas

Surveys in some areas of Svalbard are incomplete. There are large areas that are not surveyed at all. In paper charts these areas are represented as white areas limited by a red dashed line and the text "Unsurveyed".  In electronic charts these areas are coded as "Unsurveyed" or as depth areas ranging from 0 meters to the deepest depth in the area.


We will strongly advise against any navigation in these areas – even if some soundings and underwater rocks are shown. The areas should be referred to as unsurveyed.

Areas inside the 50 meters depth contour in areas with old surveys are not safe. When navigating in such areas the utmost caution should be exercised as, there are no comprehensive sea measurements available.

In newly surveyed areas of Svalbard, the surveying is performed at depths deeper than 3 meters only. Shallow areas are not surveyed.

Refer to the Warnings and Source diagram in the Charts.

Terms Used When Issuing Charts

The following terms are used when referring to the issue of charts. The text is in accordance with the International Hydrographic Organization's (IHO) publication S-4 "Chart Specifications of the IHO", Section B-100, point 128.

New Chart

The New Chart is the first publication of a chart that either:

Embrace an area not previously chartred by that nation to be scale showing. Embrace an area different from existing chart of that nation Consist of a modernised version (in terms of symbology an general presentation) of an exixting chart Consist of the adoption by that nation of an international (INT) or national chart, first published by another nation

A new chart makes existing edition obsolete.

New Edition (NE)

A new edition is a new issue of an existing chart, containing amendments essential to navigation, which may include changes additional to those in the Norwegian Notice to Mariners (Efs).

A new edition will render the existing edition of the chart obsolete.

1.1 Terms Used When Issuing Charts

The following terms are used when referring to the issue of charts. The text is in accordance with the International Hydrographic Organization's (IHO) publication S-4 "Chart Specifications of the IHO", Section B-100, point 128.

New Chart

The New Chart is the first publication of a chart that either:

Embrace an area not previously chartred by that nation to be scale showing.
Embrace an area different from existing chart of that nation
Consist of a modernised version (in terms of symbology an general presentation) of an exixting chart
Consist of the adoption by that nation of an international (INT) or national chart, first published by another nation

A new chart makes existing edition obsolete.

New Edition (NE)

A new edition is a new issue of an existing chart, containing amendments essential to navigation, which may include changes additional to those in the Norwegian Notice to Mariners (Efs).

A new edition will render the existing edition of the chart obsolete.

2 About Etterretninger for sjøfarende (Efs)

The Norwegian notices to mariners, Etterretninger for sjøfarende (Efs), is published twice a month. The Efs provides information on changes or defects in aids to navigation, discovery of new dangers and on shortcomings in Norwegian charts or publications, navigational warnings, gunnery exercises or other information of interest to mariners. I addition to temporary (T) and preliminary (P) notices in Norwegian waters.

The complete pdf editions of the Efs are accepted as an official Norwegian "notices to mariners" by the Norwegian Maritime Authority, on the same terms as the former printed Efs.

The Efs and tracings are available, free of charge, through the digital Efs service,

2.1 Professional users

Users are responsible for downloading the latest pdf edition of the Efs on

2.2 Digital Efs Service

The digital Etterretninger for sjøfarende (Efs) service has made it possible for the users to easily search for chart corrections and notices for each of the Norwegian charts. Searches can be saved for your next visit on the site. The Efs editions and tracings are available for download, free of charge.

It's possible to search for notices published in the Efs back to 2010. Please note that errors may occur in older notices, then it's the pdf edition of the Efs that's current.

Notices published before 2010 are only available through the pdf editions of the Efs.

Browse the historical archive, comprising Efs editions back to 1994.

2.3 Efs – Contents

All published information and chart corrections in the Norwegian Notices to Mariners, Etterretninger for sjøfarende (Efs) refer to the latest edition of the chart.

Contributors of nautical information to the Efs

The main contributors of nautical information to the Efs, can be divided into three groups:

  • Government agencies such as: The Norwegian Coastal Administration, The Norwegian Public Roads Administration, The Directorate of Fisheries, Port Authorities, and local municipalities. Typical data are lights and aids to navigation, bridges, fish farms, quays, fillings and moles, etc.
  • Private entrepreneurs constructing new or making changes to existing infrastructure which may affect the safe navigation at sea. This includes new/modified quays, marinas, moles, marine farms, fillings, overhead cables, submarine cables, etc.
  • Private companies or persons making constructions at sea that are not relevant for safe navigation, but where the object can be damaged by anchoring or by fishing activity, such as submarine pipelines, cables or oil-related equipment on the seabed.

The charts affected by a notice are listed in the notice heading and is repeated in the bottom of the notice. A star (*) adjacent to the number of a notice indicates that the notice is based on Norwegian original information. Chart corrections are translated into English. Other notices of importance for the navigation are translated into English in a shortened version.

The contents in Etterretninger for sjøfarende (Efs) are sorted by

All corrections of significant navigational importance and other temporary (T) and preliminary (P) notices regarding sailing in Norwegian waters are announced in the Efs:

Information about Norwegian charts and nautical publications
Read more about charts and publications in chapter 1.

Permanent chart corrections for Norwegian Waters and ocean areas
New lights and amendments to existing ones
Fixed and floating navigation aids
Newly identified shallows
New or amended submarine cables and pipelines
Overhead structures
Wrecks or obstacles

Temporary (T) and preliminary (P) notices for Norwegian Waters and ocean areas
Planned or amendments at light and navaids.
Light and navaids temporarily out of order.
Planned or amendments in ports and fairways
Warnings of planned discontinued light and navaids
Marine site surveys

Miscellaneous notices
Gunnery exercises, warnings, seismic surveys and information regarding any orders and regulations regarding sailing in certain areas

In addition will information about quality in Norwegian charts, chart date etc. be repeated at regular intervals.

Regions in the Efs

The contents in search and chaptering in the Efs pdf edition are arranged in the following areas: Norwegian Waters, the North Sea, Skagerrak, Kattegat, North Atlantic Ocean, Norwegian Sea westwards to Iceland, Arctic Ocean – the Barents Sea to Greenland, and Svalbard.

Within the area Norwegian Waters, the notices are sorted by their area, prior to their respective chart numbers.

See illustration of the Norwegian Coastal Areas (pdf, 180 kB).

See illustration of the Norwegian Ocean Areas  (pdf 344 kB).

Temporary (T) and Preliminary (P) Notices

A Temporary (T) Notice to Mariners is used to promulgate navigationally significant information that will remain valid only for a limited period. All T notices which have an indicated time will not be repeated unless any changes in time or other important changes.

A Preliminary (P) Notice to Mariners is issued to promulgate navigationally significant data early that is of importance to navigation and which in the future will result in a permanent chart correction.

These notices are indicated by (T) or (P) before the notice number, the charts will not be corrected, but an ECDIS revision (ER) are available for Electronic Charts. All active T and P notices are available on the Efs Internet service,


Positions are given in World Geodetic System (WGS84 DATUM) in degrees, minutes and decimals of minute.
Bearings are true, reckoned clockwise from 000° to 360°.
Light sectors: Bearings referring to a light sector are given in true degrees as observed from sea.
Distances are given in meters (m) or nautical miles (M).
Depths and heights are given in metres.


The publication Symbols and Abbreviations on Norwegian Maritime Charts provides an overview of symbols and abbreviations used for Norwegian nautical charts. The text is in both Norwegian and English.

2.4 Nautical Publications

Norwegian nautical publications, in addition to the Norwegian notices to mariners, Efs:

«All ships shall carry adequate and up-to-date charts, sailing directions, lists of lights, notices to mariners, tide tables and all other nautical publications necessary for the intended voyage.» (See SOLAS Consolidated Edition, Chapter V, Regulation 27).

3 Tracings

The Norwegian Hydrographic Service offers a tracing service. Tracings are supplements to the Efs notice, and are meant to aid the mariner when correcting charts and to reduce the workload. We offer tracings for charts in the Main- and Harbour chart series.

The tracings can be downloaded from the Efs Internet service, free of charge. The users themselves must print the tracings. It is possible to download all tracings corresponding to the latest issue of the Efs in the pdf archive.

An instruction video on how to use tracings is available in Norwegian.

Tracing User Guide

The tracings are meant as a supplement to the notices to mariners only. They should be used in conjunction with the corresponding notice. Which notice the tracing corresponds to, is written on the lower right corner of the tracing. Which chart the tracing refers to, will also be indicated in the same area of the tracing.

When printing the tracing, make sure the printer is set up to print with no scaling. The tracing should be placed correctly on the chart primarily by means of the tracing grid. The tracing grid corresponds to the chart grid. Latitude and longitude are noted on the tracing to make it easier to place it.

The charts are printed on paper which is a living material. The size of the chart will change with the weather, and the user might observe a difference in size of the chart and the tracing. When this error is observed the user should place the tracing by using the grid intersection closest to the object inserted, amended or deleted. If the grid intersection is too far away from the object, the tracing should be placed by means of the reference features closest to the object being amended. If the tracing is placed in this way, the user must insure that the tracing and chart grids are parallel to each other. This is especially important when making amendments to light sectors in order to ensure that the sector angles are drawn correctly.

When the tracing has been placed correctly you can use the pointed end of dividers/compasses to perforate the tracing and mark in the chart where the new appropriate object should be placed. The deletion of an object will be shown in the tracing by use of a deletion symbol (x) and a corresponding text. When the tracing is placed on the chart, the object to be deleted will lie directly beneath the deletion symbol.

4 Nautical Charts

Nautical charts are the foundation for safe navigation. When navigating narrow channels, charts in the largest scale available should always be used as these give the best and most detailed information about the waters. Smaller scale charts are very simplified and are not edited to support navigation in coastal waters.

The publication date can be found in the title area. This date will provide the user with a guideline to how reliable the chart is. Please check the "Printing and Maintenance" section for further information.


Due to the rapid development of both shipping and electronic navigational aids, the demand for reliability in nautical charts is now greater than ever. The chart reliability is very much dependent on the technology available to the hydrographical service.

Charts based on older surveys do not fully meet today's reliability standards. Therefore, Norwegian Hydrographic Service frequently receive discrepancy reports. These reports are promptly handled.

If required, a notice will be published in the Etterretninger til sjøfarende (Efs). Nautical charts are updated at the next print.

Updating and Printing of Charts

The year of publication is shown in the title block. This information will help the mariner in judging the reliability of the chart. As charts are subject to frequent changes, they are reprinted regularly.

The month and year of printing as well as the latest Notices to Mariners it is updated to,is shown in the lower left-hand corner of the chart. See example below.  "POD: 22. Dec 2016. Corrected to "Efs" No 23/16." means that map file is generated 22.12.2016 and the notices published in Efs no. 23/16 is corrected in the chart.

Hydrographic charts on paper are now sold only as POD-Charts (Print on demand) and must be ordered from authorized POD dealers. Charts are subject to frequent changes, and important amendments are continuously published in the Norwegian Notices to Mariners, Etterretninger for sjøfarende (Efs).

It is therefore the responsibility of the mariners to keep their charts updated in accordance with Efs after the date of printing. A Norwegian chart is updated when all corrections from the Efs concerning that chart are applied.

Overview with printing dates for Norwegian charts (pdf).

Print on Demand (POD)

The Norwegian Hydrographic Service offers a Print on Demand (POD) service. Print on Demand service is offered for all Norwegian charts and can be purchased from approved suppliers of The Norwegian Mapping Authority's maps and charts.

Traditionally, paper charts were issued every few years. As time passes, there would be messages from the Norwegian Notices to Mariners, Etterretninger for sjøfarende (Efs), that were not reflected in the chart at selling time. This meant that even though the chart was bought today, many important corrections could have been issued since the chart was printed, and mariners had to manually update the chart with the Efs updates since the chart was published. With POD this is no longer necessary, as POD-charts are automatically and continuously updated to the latest Efs.

When a POD chart is purchased, the mariner only has to review the Efs’ published after the POD production, in order to have a fully updated chart. This will typically be limited to the latest Efs.

Chart updating starts as soon as an Efs is published. All updates shall be performed before the next Efs is issued (i.e. during a 14 day period). POD charts may also include updates that have not yet been published in an Efs.

POD: "Print on Demand" is printed in red text on the left and right side of the chart frame. A text box in the lower left corner displays different dates and Efs reference.

Source diagram in charts

The source diagram printed in the chart title box shows when the survey was performed and the quality of the depth data. This provides an indication of the accuracy of the product. Areas surveyed before about 1960 did not receive full seafloor coverage and depth anomalies may be expected.

There may be undiscovered depths in older surveyed areas. Caution must therefore be taken when sailing in these areas. It is dangerous to sail outside marked areas/recommended track.

4.1 Symbols and Abbreviations

The publication Symbols and Abbreviations on Norwegian Maritime Charts provides an overview of symbols and abbreviations used for Norwegian nautical charts. The text is in both Norwegian and English.


All nautical charts in the scale 1:50 000 or larger are projected in Gauss conform cylinder projection (Gauss-Krüger). Nautical charts in scales less than 1:50 000 are usually constructed in a Mercator projection.

Chart Scale

Norwegian Hydrographic Service publishes navigational charts over Norwegian and bordering waters. The charts are mostly based on Norwegian hydrographic surveys.

Navigational charts are published in the following scales:

  • Main chart series 1:50 000 – 1:100 000
  • Harbour chart series 1:5 000 – 1:25 000
  • Coastal chart series 1:200 000 – 1:350 000
  • General chart series 1:700 000 – 1:10 000 000

Chart datum

From Utsira and northwards, including Svalbard, the chart datum (vertical) is identical to "lowest astronomical tide" (LAT). In Oslofjorden (north of Drøbaksundet) the chart datum is 30 cm below LAT, and between the Swedish border and Utsira the chart datum is 20 cm below LAT.

Meteorological conditions can cause depths to be less than specified in the chart. More information can be found in the publication Tide Tables for the Norwegian Coast and Svalbard (Tidevannstabeller for den norske kyst med Svalbard) and in the Norwegian pilot guide sailing directions, Den norske los, Volume 1, Alminnelige opplysninger.

On the Swedish side of nautical chart no.1 the soundings refer to a different datum, and they are approximately 60 cm shallower than the Norwegian ones. When navigating Swedish waters, Swedish charts should be used. Observed water levels and water level forecasts for the next days are available at Se havnivå. The service also provides tide tables and vertical reference levels.

Place names

In some charts the spelling of place names are out dated. Place names are currently under revision and creation.

When new releases of charts are published, all place names will be revised and updated.  It will therefore take a while before all the charts are updated.  There is currently a transition period with maps and publication using both the old and new spellings of certain place names.

In new editions of charts place names a will be updated in accordance with the laws on place names.

Leading Line

Leading lines indicate that waters are commonly used as fairways.

Ferry route

To inform mariners of crossing traffic, ferries are marked on the chart by the contours of a red ferry along a dashed line. This symbol is not to be regarded as a recommended track.

Overhead- and Submarine Cables

Overhead cables, telephone and power lines that cross salt water are inserted onto the nautical charts after if Norwegian Hydrographic Service is notified about them. Notices about new cables are frequently issued in Efs.

As both overhead and underwater cables may carry very high voltages, it is important that the navigator show extreme caution when navigating near them. The navigator should also be aware that new cables may not be displayed in the chart.

Underwater and overhead cables which are installed after the latest print of the chart have to be inserted manually.

Depth Contours

The depth contours have been drawn through points with the same depth, and have then been generalized. Thus, the contours may not always be accurate, but they do show the nature of the topography of the sea floor. By generalizing the depth contours, the line is always moved towards deeper waters to ensure safe navigation.

In areas where the topography is complicated, normal cartographic practice is to merge or generalize the depth areas. This is very common in the complex Norwegian waters.


A sounding is the depth in a position relative to the chart's vertical datum. Its value is a positive number. Its position is the centre of the number.

Underwater rocks

An underwater rock is an area of limited size which stretches towards the surface, but is deeper than 0,5 m below the chart's vertical datum.

0 – 9,9 m are displayed with decimals.

10 – 20 m are rounded down to the nearest meter

> 20 m are displayed as soundings, in italics.

Rock awash

A rock awash is a rock which lies between chart's vertical datum and 0.5 meters below chart's vertical datum.


A rock is covered and uncovered by water. Its height is above the chart's vertical datum.

Danger Line

The Norwegian "danger line in general" is still in use in some areas of several of our charts.

In sheltered waters, it is a dotted line which indicates an approximate depth of 6 m.

In more open waters, it may be drawn in deeper waters, normally 6 to 20–30 m.

Intertidal Areas Above Chart Datum

The area of the seafloor between 0,5 m below the chart's vertical datum and the coastline. This area is limited by the Charts Low Waterline.


The coastline (the border between sea and land) in Norwegian charts is defined to be Mean High Water.

Depth Over Wreck

Wrecks and large debris on the seafloor may over the course of time have shifted so much that the depth above such wrecks may be less than the charted depth.

4.2 Reference Level for Vertical Clearances

The reference level for vertical clearances in Norwegian charts is the highest astronomical tide (HAT). Analysis has shown that the tidal levels in Norway often exceed this level. Therefore extra safety margins should be added by navigators in order to ensure safe navigation.

By increasing the safety margins by the following amounts in the designated areas, the vertical clearance should be safe:

  • Inner Oslofjorden (North of Drøbaksundet): 80 cm
  • From the Swedish border to Hordaland: 50 cm
  • From Hordaland to the Russian border: 30 cm

Observed water levels and water level forecasts for the next days are available at Se havnivå. The service also provides tide tables and vertical reference levels.

Download illustration showing reference levels in Norwegian charts (Norwegian text), pdf 87 kB (opens in a new window).

More information on the Norwegian tides can be found at:

Read more about tidal waters.

4.3 Submarine Cables, Overhead Cables and Submarine Pipelines

Both submarine and overhead cables can carry very high voltages, and mariners should be careful when navigating near them. They should also be aware that submarine and overhead cables may not be displayed in the charts. The vertical clearance may also vary due to extreme weather conditions.

Damage to Submarine Cables

Mariners should avoid anchoring and fishing in areas where a submarine cable is displayed on the chart. Anchors and fishing gear can cause severe damage, and disrupt telecommunications or the power supply.

Damage to Submarine Pipelines

Gas from a damaged oil or gas pipeline could cause an explosion, loss of a vessel's buoyancy, serious pollution or other hazards.

Pipelines on the seafloor are not always buried and their presence may effectively reduce the charted depth by as much as 2 meters. They may also span seabed undulations and cause snagging, putting a vessel in severe danger.

Trawling across pipelines at angles of 45° or more is recommended.

4.4 Marine Farms. Moorings

Fishing within 100 m, and sailing within 20 m of a marine farm is prohibited.

The chart symbol for a marine farm is used only where a license has been given by the Directorate of Fisheries. A marine farm may not be located in the given position as one company may have been given several licenses and alternate between these locations. Some marine farms may not be charted.

The moorings may stretch for several thousand meters from the marine farm. Not all of them are displayed in the charts.

Additional information can be found at the Directorate of Fisheries' website.

5 Electronic Navigational Charts (ENC)

In connection with new surveying of the Norwegian coast, the Norwegian Hydrographic Service is prioritizing the publication of electronic navigational charts authorized for navigation. The international designation of such charts is ENC (Electronic Navigational Chart).

ENCs are produced in accordance with the International Hydrographic Organization's (IHO) S-57 standard, which is applied by all hydrographic offices world-wide for the production of corresponding electronic navigational charts for their waters.

ENCs for the entire Norwegian coast are available through authorized PRIMAR distributors. Information about coverage and overview of distributors is available from

5.1 Electronic Chart Display and Information System (ECDIS)

ECDIS is a certified navigation system meeting SOLAS requirements to navigational equipment pursuant to certain criteria. If an ENC is installed on this type of system and kept updated, it may be used for navigation in the same manner as an updated paper nautical chart.

Other types of unofficial electronic charts, for example charts produced by private industry or raster charts, can only be used as a supplement for navigation.

The following back-up systems are approved for use on Norwegian vessels:

  1. Updated paper nautical charts, or
  2. ECDIS No. 2 connected to an emergency power source.

IMO requirements for mandatory use of ECDIS

The International Maritime Organization's (IMO) Maritime Safety Committee (MSC) approves provisions regarding the mandatory use of ECDIS, depending on the type of vessel and its size.

5.2 Official Norwegian Electronic Navigational Charts (ENC) for Norwegian Waters – Content and Updating

Official electronic navigational charts (ENC) are vector charts produced in compliance with the specifications given by the International Hydrographic Organization, and are approved by a national hydrographic office.

The sources for Norwegian ENCs are either digitalized or scanned analog charts, or a database. The data is compiled into a seamless database in which each ENC is a cell. Each cell is identified by a unique number.

The content of charts and ENCs in the same area is not always identical. The ENC often contains more detailed data.

Depths along the quay

Quay depth is not a object class in the ENC. They are regular soundings showing its true position. Quay depths are taken either on the quay or two meters away from the quay depending on when the measurements were taken. Quay depths maybe presented slightly away from the quay in the electronic navigational chart (ENC) in order to improve readability in ECDIS.

Update Files (ER Updates)

An advantage with ENCs is the possibility for automatic updates. Update files (ER) are issued every fortnight. Within a 14 day period, all notices from the last Notice to Mariners (Efs) will be included. The ERs may also include updates that have not been issued in the Efs.

Temporary (T) and preliminary (P) notices are distributed for the ENCs in the same way as other updates. All ER updates are distributed through PRIMAR. For larger updates New Editions of an ENC will be issued. A New Edition may also be issued for technical reasons.

Terms Used

New dataset: ENC dataset that has not been issued for navigational purposes earlier.

Update: Amendments to existing dataset.

New edition: It also includes new data that have not been released earlier, in addition to all the previous updates.


Use of modern equipment makes it possible to extend the use of nautical chart information beyond what it is intended for. We strongly advise against this.

It is at all times the mariners own responsibility to familiarize themselves with and use the information in a chart in a responsible manner. Do take into consideration the constraints of the information the charts provides.

Report Feedback on Norwegian ENCs

Report errors, omissions or suggest improvements on the Norwegian Electronical Navigational Charts (ENC) in the web-based feedback system ENC Improver.

ENC Improver has been designed to provide users with a simple system to give feedback on Norwegian ENCs. Everybody who has an ENC license for navigation will receive user access to ENC Improver through their supplier.

Add a point on the chart in ENC Improver and describe the problem. A monitoring system is in place to follow up received feedback. To submit feedback, Internet access is required.

In addition to ENC Improver, errors, omissions or suggestions for improvements on the Norwegian ENCs can also be sent to

User Bands

Norwegian ENCs are divided into the following user bands:

User bands
Navigational purposeNameScale RangeUsed in Norwegian ENCsMatching Scale Range
1 Overview <1:1 499 999 1 500 000 200 NM, 96 NM
2 General 1:350 000 – 1:1 499 999 700 000, 350 000 48 NM, 24 NM
3 Coastal 1:90 000 – 1:349 999 180 000, 90 000 12 NM, 6 NM
4 Approach 1:22 000 – 1:89 999 22 000 3 NM, 1.5 NM
5 Harbour 1:4000 – 1:21 999 12 000, 8000 0.75 NM, 0.5 NM, 0.25 NM
6 Berthing > 1:4000 3999 and larger < 0.25 NM

5.3 Zones of Confidence - ZOC Diagram

The data sources for an ENC will for many areas be based on old hydrographic data with inferior positional accuracy compared to what is possible with modern technology. These areas are identified by the use of Zones of Confidence (ZOC).

In digital charts the data quality is specified in Zones of Confidence (ZOC).

The ZOC diagram describes the quality of the bathymetry in the different areas. There are five quality categories in the ZOC diagram (A1 to D).

Until autumn 2013, mainly category B and C are used for Norwegian coastal waters based on the following classifications: ENCs with source data from older surveying (before 1960) are given ZOC value C, while ENCs with source data from surveying younger than ca 1960 are given ZOC value B.

From 1st of January 2014 the areas measured with multibeam sonar and which otherwise meets the requirements will be given the categories A1 or A2. The delimitation of the different zones will be added in the ENCs to always show which zone you are in.

Navigators must show great care when using (D)GPS and electronic charts in areas with older surveys as accuracy and completeness of the depth indicators are not in accordance with modern standards.

Additionally, the navigators should ensure that navigation at all times is conducted with good safety margins and in accordance with proper navigational practices.

For a full description: S57 IHO Transfer Standard for Digital Hydrographic Data.

ZOC Category
ZOC1 Position Accurancy2 Depth Accurancy3 Seafloor Coverage Typical Survey Characteristics5
A1 ± 5 m + 5% depth = 0.50 + 1%d Full area search undertaken. Significant seafloor features detected4 and depths measured. Controlled, systematic survey6 high position and depth accuracy achieved using DGPS or a minimum three high quality lines of position (LOP) and a multibeam, channel or mechanical sweep system.
Depth (m) Accurancy (m)

100 1000

± 0.6
± 0.8
± 1.5
± 10.5

A2 ± 20 m = 1.00 + 2%d Full area search undertaken. Significant seafloor features detected4 and depths measured. Controlled, systematic survey6 achieving position and depth accuracy less than ZOC A1 and using a modern survey echosounder7 and a sonar or mechanical sweep system
 Depth (m) Accurancy (m)
100 1000
± 1.2
± 1.6
± 3.0
± 21.0
B ± 50 m = 1.00 + 2%d   Full area search not achieved; uncharted features, hazardous to surface navigation are not expected but may exist. Controlled, systematic survey achieving similar depth but lesser position accuracies than ZOC A2, using a modern survey echosounder5, but no sonar or mechanical sweep system.
Depth (m) Accurancy (m)
100 1000

± 1.2
± 1.6
± 3.0
± 21.0

C ± 500 m = 2.00 + 5%d Full area search not achieved, depth anomalies may be expected. Low accuracy survey or data collected on an opportunity basis such as soundings on passage.   
Depth (m) Accurancy (m)
100 1000

± 2.5
± 3.5
± 7.0
± 52.0

D worse than ZOC C worse than ZOC C Full area search not achieved, large depth anomalies may be expected. Poor quality data or data that cannot be quality assessed due to lack of information.
U Unassessed – The quality of the bathymetric data has yet to be assessed


To decide on a ZOC Category, all conditions outlined in columns 2 to 4 of the table must be met.

Explanatory notes quoted in the table:

1 The allocation of a ZOC indicates that particular data meets minimum criteria for position and depth accuracy and seafloor coverage defined in this Table. ZOC categories reflect a charting standard and not just a hydrographic survey standard. Depth and position accuracies specified for each ZOC category refer to the errors of the final depicted soundings and include not only survey errors but also other errors introduced in the chart production process. Data may be further qualified by Object Class 'Quality of Data' (M_QUAL) sub-attributes as follows:

a) Positional Accuracy (POSACC) and Sounding Accuracy (SOUACC) may be used to indicate that a higher position or depth accuracy has been achieved than defined in this Table (e.g. a survey where full seafloor coverage was not achieved could not be classified higher that ZOC B; however, if the position accuracy was, for instance, ± 15 metres, the sub-attribute POSACC could be used to indicate this).

b) Swept areas where the clearance depth is accurately known but the actual seabed depth is not accurately known may be accorded a 'higher' ZOC (i.e. A1 or A2) providing positional and depth accuracies of the swept depth meets the criteria in this Table. In this instance, Depth Range Value 1 (DRVAL1) may be used to specify the swept depth. The position accuracy criteria apply to the boundaries of swept areas.

c) SURSTA, SUREND and TECSOU may be used to indicate the start and end dates of the survey and the technique of sounding measurement.

2 Position Accuracy of depicted soundings at 95% CI (2.45 sigma) with respect to the given datum. It is the cumulative error and includes survey, transformation and digitizing errors etc. Position accuracy need not be rigorously computed for ZOCs B, C and D but may be estimated based on type of equipment, calibration regime, historical accuracy etc.

3 Depth accuracy of depicted soundings = a + (b*d)/100 at 95% CI (2.00 sigma), where d = depth in metres at the critical depth. Depth accuracy need not be rigorously computed for ZOCs B, C and D but may be estimated based on type of equipment, calibration regime, historical accuracy etc.

4 Significant seafloor features are defined as those rising above depicted depths by more than:

a. <40 m 2 m
b. >40 m 10% depth

A full seafloor search indicates that a systematic survey was conducted using detection systems, depth measurement systems, procedures, and trained personnel designed to detect and measure depths on significant seafloor features. Significant features are included on the chart as scale allows. It is impossible to guarantee that no significant feature could remain undetected, and significant features may have become present in the area since the time of the survey.

5 Typical Survey Characteristics - These descriptions should be seen as indicative examples only.

6 Controlled, systematic surveys (ZOC A1, A2 and B) - surveys comprising planned survey lines, on a geodetic datum that can be transformed to WGS 84.

7 Modern survey echo sounder - a high precision single beam depth measuring equipment, generally including all survey echo sounders designed post 1970.".

6 Tidal Waters

Observed water levels, water level forecasts, tide tables and vertical reference levels for the Norwegian coast are available at Kartverket’s service Se havnivå

The water level is composed of the astronomical tide, caused by the gravitational interactions between the moon, sun and earth, and the surge (positive or negative) caused by meteorological effects such as pressure and wind.

The Lowest Astronomical Tide (LAT) and the Highest Astronomical Tide (HAT) refers to the lowest and highest tide level which can be predicted to occur under average meteorological conditions. LAT and HAT are determined by finding the lowest low water and the highest high water from 19 years of predicted tides.

Reference Level for Depths and Heights in the Tidal Tables

The vertical Chart Datum in Norwegian waters is based on the Lowest Astronomical Tide (LAT). In areas where the meteorological contribution can dominate the water level for longer periods of time, an extra safety margin has been added so that the datum is lower than LAT.

For Norwegian waters, the Chart Datum is defined as follows:

  • From Utsira and north to the Russian border (including Svalbard) Chart Datum equals LAT.
  • From the Swedish border to Utsira, Chart Datum is 20 cm lower than LAT.
  • In inner Oslofjorden north of Drøbaksund, Chart Datum is 30 cm lower than LAT.

This definition of Chart Datum was introduced into the Norwegian charts in January 2000. The datum of charts made prior to this date refer to Mean High Water Spring.



7 Information from the Norwegian Coastal Administration

The Norwegian Coastal Administration (NCA) is responsible for providing aids to navigation, pilot services, VTS services and pollution prevention in Norway. Read more about the Norwegian Coastal Administration at

Norwegian List of Lights

The latest printed issue of the Norwegian list of lights (Fyrlisten) was issued in 2018 and supersedes all previous editions.

A digital version of the Norwegian list of lights is updated every morning. You can download the continuously updated Norwegian list of lights as a pdf-file at

The Norwegian list of lights (Fyrlisten) describes operational data for aids to navigation along the Norwegioan coast. In addition, it provides general guidance regarding typically used marks in Norway, and their intendes functions.

Transition to IALA Standard for sector lights

In the period 2019 to 2025, the Norwegian Coastal Administration will be reorganizing the sectors of all the sector lights. Around 1900 sector lights will be modified to be in compliance with the standard defined by IALA (International Association of Lighthouse Authorities).

This change will require extra attention from the mariners, as all sector lights will be affected. Mariners are requested to pay careful attention to the Norwegian notice to mariners, as both color and width of light sectors may change.

More information about the IALA standard and contacts are listed on the Norwegian Coastal Administration webpage,

Buoys and Beacons

None of the Norwegian aids to navigation are manned, some have remote monitoring, but most have only periodic maintenance inspections. Beacons are built with or without lights. Most of the beacons without lights, are ironpoles in the water placed on/near shallow areas. Some beacons at land are unlit, these are beacon towers (stone) or lattice beacons. Some of the most exposed unlit marks (ironpoles), do not have any topmarks. This is due to likelihood of frequent weather damages. Beacons with lights are often lanterns on ironpole(s), or sector lights. Many of these lights have flood lights. Floating marks might have a light or be unlit. Floating marks might get off positon (due to wind and currect), and mariners are requested to apply extra care when using these marks when fixing own ship position.

Mariners are advised that aids to navigation must not be used for mooring. This can cause the aids to become damaged or out of position.


A modern Racon normally respond to both "X" and "S" frequency band radars. The range is dependent on the elevation of the radar antenna and of the transponder. Response intervals will vary depending on the characteristics of the racon. For example 18/30s means that the racon will respond for 18 seconds, and be nonresponsive for 12 seconds every 30 seconds.

A list of Racons on the Norwegian coast can be found in the Norwegian List of Lights.

Floodlights (IB)

Floodlight has a steady yellow or white light that illuminate an area. This area can be an rock, pier head, bridge piers or the structure the light is mounted on.

The purpose of the diffuser is to provide the mariner a certain effect of navigation at day, where one can better see and judge the distance to a restricted area/object and also see an illuminated daymark even though it is dark. Most recently, it is common to illuminate the stricture. This often amplified using reflectors and/or white color on the structure..

NCA Maintenance Vessels

To be able to perform their work, it is sometimes necessary for the Norwegian Coastal Administration's maintenance vessels to moor beside navigational aids. During these operations, these maintenance vessels will have restricted ability to maneuver, and the crew may be conducting dangerous operations.

In order to avoid injury and damage to personel or equipment, other vessels are requested to give these maintenance vessels as wide a berth as possible when passing them and to reduce speed as required.

7.1 Navigational warning service

The Norwegian Coastal Administration is the national coordinator for navigational warnings and provide warnings to ships containing urgent information relevant to safe navigation.

Obligation to report information relevant to safe navigation

Mariners are obliged to warn nearby vessel when aware of navigational hazards and failures of important aids to navigation. Furtermore, mariners must notify the Norwegian Coastal Administration as national coordinator for navigational warning of such hazards and failures.

Failures of aids to navigation or other navigational hazards shall be reported to the national coordinator by phone (00 47) 22 42 23 31, fax (00 47) 22 41 04 91 og by email:

Broadcast of navigation warnings

In Norwegian sea- and coastal waters, three types of navigational warnings are promulgated, NAVAREA warnings, coastal warnings og local warnings.

NAVAREA warnings are concerned with the information, which oceangoing mariners require for their safe navigation. NAVAREA warnings are broadcast by the SafetyNET and SafetyCast (medio 2020) satellite services.

Coastal warnings are broadcast by the International NAVTEX service and concerns information, which is necessary for safe navigation within areas seaward of the fairway buoy or pilot   station. The Norwegian coast is covered by six NAVTEX stations, Svalbard, Vardø, Bodø, Ørlandet, Rogaland og Jeløya. Coastal warnings are also broadcast by the coastal radio service on VHF voice.

Local warnings broadcast supplement coastal warnings by giving detailed information within inshore waters, often within the limits of a VTS area or the jurisdiction of a harbour or port authority. Local warnings are broadcast using VHF voice.

NAVAREA warnings and coastal warnings are available on the website of the Norwegian Coastal Administration, The publication of navigation warnings on this website is not intended as a substitute for, or alternative to the satellite service or NAVTEX, and does not relieve mariners from their responsibility to comply with MSI broadcasts in accordance with the provisions of SOLAS.

7.2 Vessel Traffic Services

The VTS contact information is listed at the Norwegian Coastal Administration's website,

There are five Vessel Traffic Service Centers covering waters along the Norwegian coast, all operated by the Norwegian Coastal Administration. There are four VTS areas in the southern and western part of Norway (Fedje, Kvitsøy, Brevik, Horten) and one area in the far north (Vardø).

An english translation of the regulations relating to sailing in the Norwegin VTS areas can be found at the website - Regulations relating to maritime traffic in specific waters

Read the regulations relating to maritime traffic in specific waters, Sjøtrafikkforskriften, in Norwegian at

7.3 Pilot Boarding

The Norwegian Coastal Administration is responsible for the state pilotage service. Pilot bookings are made electronically in the SafeSeaNet Norway messaging service on

For more information about the Norwegian pilot services, visit the Norwegian Coastal Administration's website

See an overview of Norwegian pilot boarding areas at

The Pilotage Act

The Compulsory Pilotage Regulations stipulate which vessels are subject to compulsory pilotage and the waters where the requirement applies. The compulsory pilotage requirement can be met by either employing a pilot or by use of a Pilot Exemption Certificate.

The general rule is that all vessels with a length of 70 metres or more are subject to compulsory pilotage when operating in waters within the baselines. Certain areas are nevertheless exempt from compulsory pilotage for vessels in transit to or from the pilot boarding area. For certain categories of vessels stricter rules apply, such as passenger vessels and vessels carrying dangerous and polluting cargo.

The Pilotage Act applies to Norwegian internal waters and the territorial sea, and it has also been made applicable to Svalbard.

Download the documents "Compulsory Pilotage Regulations – unofficial translation" and "Pilotage Act – unofficial translation" at

Read the Pilotage Act, lospliktforskriften, in Norwegian at

7.4 Ice Service

The Norwegian Coastal Administration provides the national Ice Service, which has two main tasks:

  • Provide ship traffic with updated information on ice conditions in Norwegian waters from the Swedish border to Kristiansand.
  • Icebreaking in main and secondary fairways..

Ice reports are available from 1 December to 31 March.

More information about the Norwegian ice service is available at

7.5 SafeSeaNet Norway – General User Information

SafeSeaNet Norway (SSN)  is Norway's Single Window portal for ship reporting. This is a messaging service for ships arriving and departing Norwegian ports. The service is operated by the Norwegian Coastal Administration.

For supplementary information visit the Norwegian Coastal Administration's website

8 Coastal Radio – Maritime Safety Information (MSI)

Coastal radio broadcasts Maritime Safety Information (MSI) and forecasts on MF primary channels, available VHF working channels and Navtex. More information at

Coastal Radio

Coastal Radio South:

  • o/Tjøme: MF primary channel Ch-251
  • o/Farsund: MF primary channel Ch-291
  • o/Rodaland: MF primary channel Ch-260
  • o/Bergen: MF primary channel Ch-272
  • o/Florø: MF primary channel Ch-256
  • o/Ørlandet: MF primary channel Ch-290

Coastal Radio North:

  • o/Sandnessjøen: MF primary channel Ch-266
  • o/Bodø: MF primary channel Ch-286
  • o/Andenes: MF primary channel Ch-249
  • o/Bjørnøya: MF primary channel Ch-270
  • o/Jan Mayen: MF primary channel Ch-277
  • o/Vardø: MF primary channel Ch-267
  • o/Berlevåg: MF primary channel Ch-261
  • o/Hammerfest: MF primary channel Ch-241
  • o/Svalbard: MF primary channel Ch-273
  • o/Svalbard HF: MF primary channel Ch-401

The nearest coastal radio station is reached by dialling telephone number 120.

From phones that require an international dialling code to call Norway the following list of direct dial numbers is useful:

Coastal Radio North: +47 75 52 89 25
Coastal Radio South: +47 51 69 00 44

All coastal radio stations receive and record Safe Sea Net messages (SSN) Arrival Notification and Reporting Point directly in the NCA SSN system.

8.1 Routines for Maritime Safety Information (MSI)

Vital and very important navigational warnings and storm warnings (force 9 and up), are notified by DSC on MF and VHF followed by advertising on VHF Ch 16 and 2,182 kHz immediately after receipt from the Meteorological Institute or The Norwegian Coastal Administration. Warnings are then readout on the announced working channels.

Important navigational warnings and strong wind warnings (less than force 9) are broadcast only on VHF Ch 16 and 2,182 kHz before being readout on the advertised working channels. Strong wind and storm warnings are repeated twice in subsequent bulletins.

Navigation alerts are repeated in the two subsequent bulletins, and then once a day (10:33 UTC) for 7 days. Besides this, the numbers of valid navigational warnings which are still inforce are broadcast in regular bulletins until cancellation.

Channel 260 (Rogaland) is not used for the regular airing of MSI messages as the area is covered by the transmitters in Farsund and Bergen.


In the Navtex system, vital and important messages are sent immediately upon receipt. Navigation warnings are repeated in the regular bulletins until cancellation. Strong wind and storm warnings are repeated once in the subsequent regular airtime.

8.2 Schedules for MSI Broadcasts

 Scheduled MSI Voice Broadcasts (UTC) at:

  • 02:33
  • 06:33
  • 10:33
  • 14:33
  • 18:33
  • 22:33 

Scheduled broadcast for Navtex (UTC)

Svalbard (A) 00001 0400 08002 12001 16003 2000 450 nm
Vardø (C) 00201 0420 0820 12201 16203 2020 450 nm
Bodø (B) 00101 0410 0810 12101 1610 2010 450 nm
Ørlandet (N) 02101 0610 1010 14101 1810 2210 450 nm
Rogaland (L) 01501 0550 0950 13501 1750 2150 450 nm
Jeløy (M)* 02001 0600 1000 14001 1800 2200 150 nm

1) Include weather forecast
2) Include ice report
3) Include ice reports on Tuesdays
* Warnings for the Oslofjord og Skagerak.

Range indicates the senders estimated range in nautical mile.

Broadcast of MSI at HF-NBDP for the Polar areas

HF NBDP (telex) dispatched by Vardø radio via transmitter on Svalbard.


  • Frequency 8416,5 kHz at 06:30 and 18:30
  • Frequency 4210,0 kHz at 06:45 and 18:45

Ice warnings over HF NBDP

Broadcast during winter time for METAREA XIX, on Tuesdays at 23.00 UTC on 8416,5 kHz and at 23:15 at 4210,0 kHz.

Scheduled broadcast for weather forecast HF NBDP METAREA-XIX (UTC):

  • Frequency 8416,5 kHz at 11:00 and 23:00
  • Frequency 4210,0 kHz at 11:15 and 23:15

8.3 Monitoring

Emergency channels

Norway does not currently monitor HF channels.

The Coast Radio Station monitors all the maritime emergency channels:

  • VHF DSC (Ch 70)
  • VHF tale (Ch 16)
  • MF DSC distress (2187,5 kHz) follow up on voice channel 2182 kHz

In addition the Coast Radio Station monitor the following channels 24-7:

  • MF DSC international (2189,5 kHz)
  • All VHF working channels

Ships are encouraged to contact the Norwegian Coast Radio Station using digital selective Call (DSC). Using MMSI 002570000 in the call, the system automatically selects the nearest Norwegian Coast Radio Station.

Termination of listening watch on MF Voice channel

From March 1 2018, Coastal Radio bends listening to all MF voice channels. From this date it will only be listened to DSC. All voice channels will still be in operation, but only after callback using DSC.

8.4 Weather forecast

Local forecast for coastal areas are broadcast on channel 16 and on VHF working channels every day at 09:00, 12:00, 15:00, 18:00 and 21:00 local time. Weather forecast for waters are not advertised on call channels.

The alerts are sent out on some of the MF channels at the advertised times:

South off 65° N:

  • Farsund (channel 291) UTC at 12:15 and 23:15
  • Rogaland (channel 260) UTC at 12:15 and 23:15
  • Bergen (channel 272) UTC at 12:15 and 23:15
  • Florø (channel 256) UTC at 12:15 and 23:15
  • Ørlandet (channel 290) UTC at 12:15 and 23:15

North off 65° N:

  • Sandnessjøen (channel 266) UTC at 12:03 and 23:03
  • Andenes (channel 249) UTC at 12:03 and 23:03
  • Jan Mayen (channel 277) UTC at 12:03 and 23:03
  • Hammerfest (channel 241) UTC at 12:03 and 23:03
  • Berlevåg (channel 261) UTC at 12:03 and 23:03
  • Vardø (channel 267) UTC at 12:03 and 23:03
  • Svalbard (channel 273) UTC at 12:03 and 23:03
  • Svalbard (channel 401) UTC at 12:03 and 23:03

Weather Forecast from MET Norway

MET Norway is the meteorological service for both The Military and the Civil Services in Norway, as well as the public.

Norwegian weather and wave forecast are available on the internet at